2. Matter is anything that has mass
and volume that occupies space
. For example, a car would be
said to be made of matter, as it
occupies space, and has mass.
4. In a solid the particles (ions,
atoms or molecules) are
closely packed together.
The force between particles
are strong so that the
particles cannot move freely
but can only vibrate.
5. As a result, a solid has
a stable, definite shape,
and a definite volume.
Solids can only change
their shape by force, as
when broken or cut.
6. A liquid is nearly
incompressible fluid that
conforms to the shape of
its container but retains
a (nearly) constant
volume independent of
pressure.
7. The volume is definite if
the temperature and press
ure are constant.
When a solid is heated
above its melting point, it
becomes liquid, given
that the pressure is higher
than the triple point of
the substance.
8. A gas is a compressible
fluid. Not only will a gas
conform to the shape of its
container but it will also
expand to fill the
container.
9. In a gas, the molecules
have enough kinetic
energy so that the effect of
intermolecular forces is
small (or zero for
an ideal gas), and the
typical distance between
neighboring molecules is
much greater than the
molecular size.
10. Matter is made of small
particles.
Particles of matter have
space between them.
Particles of matter are
continuously moving.